The foundation, based in Madison, Wis., sent the letter after an unidentified local resident complained to the group, staff attorney Patrick Elliott said.

"Every 2012 prayer so far has been given 'in Jesus' name,'" Elliott wrote to the commission, and he asked commissioners to stop holding official prayers before meetings.

"Myself and others feel that this is a separation of church and state issue and it is also a matter of policy for the Hamilton County Commission," Coleman said. "This has nothing to do with my religious belief or lack thereof. They are specifically praying in a Christian manner, which is OK, except that they are acting in an official capacity."

Such prayers exclude residents who are Jewish, Muslim, Mormon and other faiths, Coleman said.

The Freedom From Religion letter argues that the commission's 2012 prayers "flagrantly exceed the constraints of the 1983 Supreme Court decision, Marsh v. Chambers, which carved out a narrow exception to the Establishment Clause for legislative prayer as a nod to history and custom."

After commissioners received the letter, County Commission Chairman Larry Henry referred the matter to County Attorney Rheubin Taylor.

Taylor said Tuesday that he reviewed the letter and will advise commissioners about the matter.

"I'm going to tell the commission at the appropriate time about it," Taylor said.

This isn't the first time a group has threatened to challenge commissioners for their displays of faith.

The American Civil Liberties Union sued the county on behalf of several residents in 2002 for posting the Ten Commandments in the county courthouse and two other buildings.

In May 2003, a federal judge ruled that displaying the plaques violated the constitutionally required separation of church and state and ordered the plaques' removal.

The judge ordered the county to pay attorney and court costs, and newspaper archives show legal bills totaled about $70,000.

Coleman said some fear they might lose their jobs or be publicly ostracized for opposing prayers at meetings.

"We know there's a great many people in this county who may be fearful to speak up," he said. "I have many friends who wouldn't dare speak up on this."